1000 resultados para Hyper complex


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Quaternionic theory has greatly been developed in recent years [1-12]. Thus, in our view, the study of trigonometric and logarithmic type quaternionic functions is important for the determination and realization of a hyper complex theory. In this paper, we intend to give a geometrical foundation for both logarithmic and trigonometric hyper complex functions based on the exponential function of quaternionic type recently introduced by Borges, Marão and Machado in their paper entitled Geometrical octonions II: Hyper regularity and hyper periodicity of the exponential function appearing. © 2011 Pushpa Publishing House.

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The authors describe on a Brazilian girl with coronal synostosis, facial asymmetry, ptosis, brachydactyly, significant learning difficulties, recurrent scalp infections with marked hair loss, and elevated serum immunoglobulin E. Standard lymphocyte karyotype showed a small additional segment in 7p21[46,XX,add(7)(p21)]. Deletion of the TWIST1 gene, detected by Multiplex Ligation Probe-dependent Amplification (MPLA) and array-CGH, was consistent with phenotype of SaethreChotzen syndrome. Array CGH also showed deletion of four other genes at 7p21.1 (SNX13, PRPS1L1, HD9C9, and FERD3L) and the deletion of six genes (CACNA2D2, C3orf18, HEMK1, CISH, MAPKAPK3, and DOCK3) at 3p21.31. Our case reinforces FERD3L as candidate gene for intellectual disability and suggested that genes located in 3p21.3 can be related to hyper IgE phenotype. (C) 2012 Wiley Periodicals, Inc.

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All plants are typically confronted to simultaneous biotic and abiotic stress throughout their life cycle. Low inorganic phosphate (Pi) is the most common nutrient deficiency limiting plant growth in natural and agricultural ecosystems while insect herbivory accounts for major losses in plant productivity and impacts on ecological and evolutionary changes in plant populations. Here we report that plants experiencing Pi deficiency induce the jasmonic acid (JA) pathway and enhance their defence against insect herbivory. The phol mutant is impaired in the translocation of Pi from roots to shoots and shows the typical symptoms associated with Pi deficiency, including high anthocyanin and poor shoot growth. These phol shoot phenotypes were significantly attenuated by blocking the JA biosynthesis or signalling pathways. Wounded phol leaves hyper-accumulated JA in comparison to wild type, leading to increased resistance against the generalist herbivore Spodoptera littoralis. Pi deficiency also triggered enhanced resistance to herbivory in wild-type Arabidopsis as well as tomato and tobacco, revealing that the link between Pi deficiency and JA-mediated herbivory resistance is conserved in a diversity of plants, including crops. We performed a phol suppressor screen to identify new components involved in the adaptation of plants to Pi deficiency. We report that the THO RNA TRANSCRIPTION AND EXPORT (THO/TREX) complex is a crucial component involved in modulating the Pi- deficiency response. Knockout mutants of at least three members of the THO/TREX complex, including TEX1, HPR1, and TH06, can suppress the phol shoot phenotype. Grafting experiments showed that loss of function of TEX1 only in the root was sufficient to suppress the reduced shoot growth phenotype of phol while maintaining low Pi contents. This indicates that TEX1 is involved in a long distance root-to-shoot signalling component of the Pi-deficiency response. We identified a small MYB-like transcription factor, RAD LIKE 3 (RL3), as a potential downstream target of the THO/TREX complex. RL3 expression is induced in phol mutants but attenuated in phol-7 texl-4 double mutants. Identical to knockout mutants of the THO/TREX complex, rl3 mutants can suppress the phol shoot phenotypes. Interestingly, RL3 is induced during Pi deficiency and is described in the literature as likely being mobile. It is therefore a promising new candidate involved in the root-to-shoot Pi-deficiency signalling response. Finally, we report that PHOl and its homologue PH01:H3 are involved in the co-regulation of Pi and zinc (Zn) homeostasis. PH01;H3 is up-regulated in response to Zn deficiency and, like PHOl, is expressed in the root vascular cylinder and localizes to the Golgi when expressed transiently in tobacco cells. The phol;h3 mutant accumulates more Pi as compared to wild-type when grown in Zn-deficient medium, but this increase is abolished in the phol phol;h3 double mutant. These results suggest that PH01;H3 restricts the PHOl-mediated root-to-shoot Pi transfer in responsé to Zn deficiency. Résumé Au cours de leur cycle de vie, toutes les plantes sont généralement confrontées à divers stress biotiques et abiotiques. La carence nutritionnelle la plus fréquente, limitant la croissance des plantes dans les écosystèmes naturels et agricoles, est la faible teneur en phosphate inorganique (Pi). Au niveau des stress biotiques, les insectes herbivores sont responsables de pertes majeures de rendement et ont un impact considérable sur les changements écologiques et évolutifs dans les populations des plantes. Au cours de ce travail, nous avons mis en évidence que les plantes en situation de carence en Pi induisent la voie de l'acide jasmonique (JA) et augmentent leur défense contre les insectes herbivores. Le mutant phol est déficient dans le transport du phosphate des racines aux feuilles et démontre les symptômes typiques associés à la carence, tels que la forte concentration en anthocyane et une faible croissance foliaire. Ces phénotypes du mutant phol sont significativement atténués lors d'un blocage de la voie de la biosynthèse ou des voies de signalisation du JA. La blessure des feuilles induit une hyper-accumulation de JA chez phol, résultant en une augmentation de la résistance contre l'herbivore généraliste Spodoptera littoralis. Outre Arabidopsis, la carence en Pi induit une résistance accrue aux insectes herbivores aussi chez la tomate et le tabac. Cette découverte révèle que le lien entre la carence en Pi et la résistance aux insectes herbivores via le JA est conservé dans différentes espèces végétales, y compris les plantes de grandes cultures. Nous avons effectué un crible du suppresseur de phol afin d'identifier de nouveaux acteurs impliqués dans l'adaptation de la plante à la carence en Pi. Nous rapportons que le complexe nommé THO RNA TRANSCRIPTION AND EXPORT (THO/TREX) est un élément crucial participant à la réponse des feuilles à la carence en Pi. Les mutations d'au moins trois des membres que composent le complexe THO/TREX, incluant TEX1, HPR1 et 77/06, peuvent supprimer le phénotype de phol. Des expériences de greffes ont montré que la perte de fonction de TEX1, seulement dans la racine, est suffisante pour supprimer le phénotype de la croissance réduite des parties aériennes observé chez le mutant phol, tout en maintenant de faibles teneurs en Pi foliaire. Ceci indique que TEX1 est impliqué dans la signalisation longue distance entre les racines et les parties aériennes. Nous avons identifié un petit facteur de transcription proche de la famille des MYB, RAD LIKE 3 (RL3), comme une cible potentielle en aval du complexe THO / TREX. L'expression du gène RL3 est induite dans le mutant phol mais atténuée dans le double mutant phol-7 texl-4. Exactement comme les plantes mutées d'un des membres du complexe THO/TREX, le mutant rl3 peut supprimer le phénotype foliaire de phol. RL3 est induit au cours d'une carence en Pi et est décrit dans la littérature comme étant potentiellement mobile. Par conséquent, il serait un nouveau candidat potentiellement impliqué dans la réponse longue distance entre les racines et les parties aériennes lors d'un déficit en Pi. Enfin, nous reportons que PHOl et son homologue PHOl: H3 sont impliqués dans la co- régulation de l'homéostasie du Pi et du zinc (Zn). PHOl; H3 est sur-exprimé en réponse au déficit en Zn et, comme PHOl, est exprimé dans les tissus vasculaires des racines et se localise dans l'appareil de Golgi lorsqu'il est exprimé de manière transitoire dans des cellules de tabac. Le mutant phol; h3 accumule plus de Pi par rapport aux plantes sauvages lorsqu'il est cultivé sur un milieu déficient en Zn, mais cette augmentation en Pi est abolie dans le double mutant phol phol; h3. Ces résultats suggèrent qu'en réponse à une carence en Zn, PHOl; H3 limite l'action de PHOl et diminue le transfert du Pi des racines aux parties aériennes.

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Dans le domaine des neurosciences computationnelles, l'hypothèse a été émise que le système visuel, depuis la rétine et jusqu'au cortex visuel primaire au moins, ajuste continuellement un modèle probabiliste avec des variables latentes, à son flux de perceptions. Ni le modèle exact, ni la méthode exacte utilisée pour l'ajustement ne sont connus, mais les algorithmes existants qui permettent l'ajustement de tels modèles ont besoin de faire une estimation conditionnelle des variables latentes. Cela nous peut nous aider à comprendre pourquoi le système visuel pourrait ajuster un tel modèle; si le modèle est approprié, ces estimé conditionnels peuvent aussi former une excellente représentation, qui permettent d'analyser le contenu sémantique des images perçues. Le travail présenté ici utilise la performance en classification d'images (discrimination entre des types d'objets communs) comme base pour comparer des modèles du système visuel, et des algorithmes pour ajuster ces modèles (vus comme des densités de probabilité) à des images. Cette thèse (a) montre que des modèles basés sur les cellules complexes de l'aire visuelle V1 généralisent mieux à partir d'exemples d'entraînement étiquetés que les réseaux de neurones conventionnels, dont les unités cachées sont plus semblables aux cellules simples de V1; (b) présente une nouvelle interprétation des modèles du système visuels basés sur des cellules complexes, comme distributions de probabilités, ainsi que de nouveaux algorithmes pour les ajuster à des données; et (c) montre que ces modèles forment des représentations qui sont meilleures pour la classification d'images, après avoir été entraînés comme des modèles de probabilités. Deux innovations techniques additionnelles, qui ont rendu ce travail possible, sont également décrites : un algorithme de recherche aléatoire pour sélectionner des hyper-paramètres, et un compilateur pour des expressions mathématiques matricielles, qui peut optimiser ces expressions pour processeur central (CPU) et graphique (GPU).

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We extend extreme learning machine (ELM) classifiers to complex Reproducing Kernel Hilbert Spaces (RKHS) where the input/output variables as well as the optimization variables are complex-valued. A new family of classifiers, called complex-valued ELM (CELM) suitable for complex-valued multiple-input–multiple-output processing is introduced. In the proposed method, the associated Lagrangian is computed using induced RKHS kernels, adopting a Wirtinger calculus approach formulated as a constrained optimization problem similarly to the conventional ELM classifier formulation. When training the CELM, the Karush–Khun–Tuker (KKT) theorem is used to solve the dual optimization problem that consists of satisfying simultaneously smallest training error as well as smallest norm of output weights criteria. The proposed formulation also addresses aspects of quaternary classification within a Clifford algebra context. For 2D complex-valued inputs, user-defined complex-coupled hyper-planes divide the classifier input space into four partitions. For 3D complex-valued inputs, the formulation generates three pairs of complex-coupled hyper-planes through orthogonal projections. The six hyper-planes then divide the 3D space into eight partitions. It is shown that the CELM problem formulation is equivalent to solving six real-valued ELM tasks, which are induced by projecting the chosen complex kernel across the different user-defined coordinate planes. A classification example of powdered samples on the basis of their terahertz spectral signatures is used to demonstrate the advantages of the CELM classifiers compared to their SVM counterparts. The proposed classifiers retain the advantages of their ELM counterparts, in that they can perform multiclass classification with lower computational complexity than SVM classifiers. Furthermore, because of their ability to perform classification tasks fast, the proposed formulations are of interest to real-time applications.

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Mutualistic interactions involving pollination and ant-plant mutualistic networks typically feature tightly linked species grouped in modules. However, such modularity is infrequent in seed dispersal networks, presumably because research on those networks predominantly includes a single taxonomic animal group (e.g. birds). Herein, for the first time, we examine the pattern of interaction in a network that includes multiple taxonomic groups of seed dispersers, and the mechanisms underlying modularity. We found that the network was nested and modular, with five distinguishable modules. Our examination of the mechanisms underlying such modularity showed that plant and animal trait values were associated with specific modules but phylogenetic effect was limited. Thus, the pattern of interaction in this network is only partially explained by shared evolutionary history. We conclude that the observed modularity emerged by a combination of phylogenetic history and trait convergence of phylogenetically unrelated species, shaped by interactions with particular types of dispersal agents.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Numerical modelling methodologies are important by their application to engineering and scientific problems, because there are processes where analytical mathematical expressions cannot be obtained to model them. When the only available information is a set of experimental values for the variables that determine the state of the system, the modelling problem is equivalent to determining the hyper-surface that best fits the data. This paper presents a methodology based on the Galerkin formulation of the finite elements method to obtain representations of relationships that are defined a priori, between a set of variables: y = z(x1, x2,...., xd). These representations are generated from the values of the variables in the experimental data. The approximation, piecewise, is an element of a Sobolev space and has derivatives defined in a general sense into this space. The using of this approach results in the need of inverting a linear system with a structure that allows a fast solver algorithm. The algorithm can be used in a variety of fields, being a multidisciplinary tool. The validity of the methodology is studied considering two real applications: a problem in hydrodynamics and a problem of engineering related to fluids, heat and transport in an energy generation plant. Also a test of the predictive capacity of the methodology is performed using a cross-validation method.

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Thesis (Ph.D.)--University of Washington, 2016-08

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The epididymis has an important role in the maturation of sperm for fertilization, but little is known about the epididymal molecules involved in sperm modifications during this process. We have previously described the expression pattern for an antigen in epididymal epithelial cells that reacts with the monoclonal antibody (mAb) TRA 54. Immunohistochemical and immunoblotting analyses suggest that the epitope of the epididymal antigen probably involves a sugar moiety that is released into the epididymal lumen in an androgen-dependent manner and subsequently binds to luminal sperm. Using column chromatography, SDS-PAGE with in situ digestion and mass spectrometry, we have identified the protein recognized by mAb TRA 54 in mouse epididymal epithelial cells. The ∼65 kDa protein is part of a high molecular mass complex (∼260 kDa) that is also present in the sperm acrosomal vesicle and is completely released after the acrosomal reaction. The amino acid sequence of the protein corresponded to that of albumin. Immunoprecipitates with anti-albumin antibody contained the antigen recognized by mAb TRA 54, indicating that the epididymal molecule recognized by mAb TRA 54 is albumin. RT-PCR detected albumin mRNA in the epididymis and fertilization assays in vitro showed that the glycoprotein complex containing albumin was involved in the ability of sperm to recognize and penetrate the egg zona pellucida. Together, these results indicate that epididymal-derived albumin participates in the formation of a high molecular mass glycoprotein complex that has an important role in egg fertilization.

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The aim of this work was to characterize the effects of partial inhibition of respiratory complex I by rotenone on H2O2 production by isolated rat brain mitochondria in different respiratory states. Flow cytometric analysis of membrane potential in isolated mitochondria indicated that rotenone leads to uniform respiratory inhibition when added to a suspension of mitochondria. When mitochondria were incubated in the presence of a low concentration of rotenone (10 nm) and NADH-linked substrates, oxygen consumption was reduced from 45.9 ± 1.0 to 26.4 ± 2.6 nmol O2 mg(-1) min(-1) and from 7.8 ± 0.3 to 6.3 ± 0.3 nmol O2 mg(-1) min(-1) in respiratory states 3 (ADP-stimulated respiration) and 4 (resting respiration), respectively. Under these conditions, mitochondrial H2O2 production was stimulated from 12.2 ± 1.1 to 21.0 ± 1.2 pmol H2O2 mg(-1) min(-1) and 56.5 ± 4.7 to 95.0 ± 11.1 pmol H2O2 mg(-1) min(-1) in respiratory states 3 and 4, respectively. Similar results were observed when comparing mitochondrial preparations enriched with synaptic or nonsynaptic mitochondria or when 1-methyl-4-phenylpyridinium ion (MPP(+)) was used as a respiratory complex I inhibitor. Rotenone-stimulated H2O2 production in respiratory states 3 and 4 was associated with a high reduction state of endogenous nicotinamide nucleotides. In succinate-supported mitochondrial respiration, where most of the mitochondrial H2O2 production relies on electron backflow from complex II to complex I, low rotenone concentrations inhibited H2O2 production. Rotenone had no effect on mitochondrial elimination of micromolar concentrations of H2O2. The present results support the conclusion that partial complex I inhibition may result in mitochondrial energy crisis and oxidative stress, the former being predominant under oxidative phosphorylation and the latter under resting respiration conditions.

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A new platinum(II) complex with the amino acid L-tryptophan (trp), named Pt-trp, was synthesized and characterized. Elemental, thermogravimetric and ESI-QTOF mass spectrometric analyses led to the composition [Pt(C11H11N2O2)2]⋅6H2O. Infrared spectroscopic data indicate the coordination of trp to Pt(II) through the oxygen of the carboxylate group and also through the nitrogen atom of the amino group. The (13)C CP/MAS NMR spectroscopic data confirm coordination through the oxygen atom of the carboxylate group, while the (15)N CP/MAS NMR data confirm coordination of the nitrogen of the NH2 group to the metal. Density functional theory (DFT) studies were applied to evaluate the cis and trans coordination modes of trp to platinum(II). The trans isomer was shown to be energetically more stable than the cis one. The Pt-trp complex was evaluated as a cytotoxic agent against SK-Mel 103 (human melanoma) and Panc-1 (human pancreatic carcinoma) cell lines. The complex was shown to be cytotoxic over the considered cells.

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FeBr2 has reacted with an equivalent of mnt2- (mnt = cis-1,2-dicyanoethylene-1,2-dithiolate) and the α-diimine L (L = 1,10'-phenantroline, 2,2'-bipyridine) in THF solution, and followed by adding of t-butyl-isocyanide to give [Fe(mnt)(L)(t-BuNC)2] neutral compound. The products were characterized by infrared, UV-visible and Mössbauer spectroscopy, besides thermogravimetric and conductivity data. The geometry in the equilibrium was calculated by the density functional theory and the electronic spectrum by the time-dependent. The experimental and theoretical results in good agreement have defined an octahedral geometry with two isocyanide neighbours. The π→π* intraligand electronic transition was not observed for cis-isomers in the near-IR spectral region.